1 files changed, 438 insertions, 0 deletions
diff --git a/libgo/go/os/file.go b/libgo/go/os/file.go
new file mode 100644
index 000000000..3f73f1dff
--- /dev/null
+++ b/libgo/go/os/file.go
@@ -0,0 +1,438 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// The os package provides a platform-independent interface to operating
+// system functionality.  The design is Unix-like.
+package os
+
+import (
+	"runtime"
+	"syscall"
+)
+
+// File represents an open file descriptor.
+type File struct {
+	fd      int
+	name    string
+	dirinfo *dirInfo // nil unless directory being read
+	nepipe  int      // number of consecutive EPIPE in Write
+}
+
+// Fd returns the integer Unix file descriptor referencing the open file.
+func (file *File) Fd() int { return file.fd }
+
+// Name returns the name of the file as presented to Open.
+func (file *File) Name() string { return file.name }
+
+// NewFile returns a new File with the given file descriptor and name.
+func NewFile(fd int, name string) *File {
+	if fd < 0 {
+		return nil
+	}
+	f := &File{fd, name, nil, 0}
+	runtime.SetFinalizer(f, (*File).Close)
+	return f
+}
+
+// Stdin, Stdout, and Stderr are open Files pointing to the standard input,
+// standard output, and standard error file descriptors.
+var (
+	Stdin  = NewFile(syscall.Stdin, "/dev/stdin")
+	Stdout = NewFile(syscall.Stdout, "/dev/stdout")
+	Stderr = NewFile(syscall.Stderr, "/dev/stderr")
+)
+
+// Flags to Open wrapping those of the underlying system. Not all flags
+// may be implemented on a given system.
+const (
+	O_RDONLY   int = syscall.O_RDONLY   // open the file read-only.
+	O_WRONLY   int = syscall.O_WRONLY   // open the file write-only.
+	O_RDWR     int = syscall.O_RDWR     // open the file read-write.
+	O_APPEND   int = syscall.O_APPEND   // append data to the file when writing.
+	O_ASYNC    int = syscall.O_ASYNC    // generate a signal when I/O is available.
+	O_CREAT    int = syscall.O_CREAT    // create a new file if none exists.
+	O_EXCL     int = syscall.O_EXCL     // used with O_CREAT, file must not exist
+	O_NOCTTY   int = syscall.O_NOCTTY   // do not make file the controlling tty.
+	O_NONBLOCK int = syscall.O_NONBLOCK // open in non-blocking mode.
+	O_NDELAY   int = O_NONBLOCK         // synonym for O_NONBLOCK
+	O_SYNC     int = syscall.O_SYNC     // open for synchronous I/O.
+	O_TRUNC    int = syscall.O_TRUNC    // if possible, truncate file when opened.
+	O_CREATE   int = O_CREAT            // create a new file if none exists.
+)
+
+type eofError int
+
+func (eofError) String() string { return "EOF" }
+
+// EOF is the Error returned by Read when no more input is available.
+// Functions should return EOF only to signal a graceful end of input.
+// If the EOF occurs unexpectedly in a structured data stream,
+// the appropriate error is either io.ErrUnexpectedEOF or some other error
+// giving more detail.
+var EOF Error = eofError(0)
+
+// Read reads up to len(b) bytes from the File.
+// It returns the number of bytes read and an Error, if any.
+// EOF is signaled by a zero count with err set to EOF.
+func (file *File) Read(b []byte) (n int, err Error) {
+	if file == nil {
+		return 0, EINVAL
+	}
+	n, e := syscall.Read(file.fd, b)
+	if n < 0 {
+		n = 0
+	}
+	if n == 0 && e == 0 {
+		return 0, EOF
+	}
+	if e != 0 {
+		err = &PathError{"read", file.name, Errno(e)}
+	}
+	return n, err
+}
+
+// ReadAt reads len(b) bytes from the File starting at byte offset off.
+// It returns the number of bytes read and the Error, if any.
+// EOF is signaled by a zero count with err set to EOF.
+// ReadAt always returns a non-nil Error when n != len(b).
+func (file *File) ReadAt(b []byte, off int64) (n int, err Error) {
+	if file == nil {
+		return 0, EINVAL
+	}
+	for len(b) > 0 {
+		m, e := syscall.Pread(file.fd, b, off)
+		if m == 0 && e == 0 {
+			return n, EOF
+		}
+		if e != 0 {
+			err = &PathError{"read", file.name, Errno(e)}
+			break
+		}
+		n += m
+		b = b[m:]
+		off += int64(m)
+	}
+	return
+}
+
+// Write writes len(b) bytes to the File.
+// It returns the number of bytes written and an Error, if any.
+// Write returns a non-nil Error when n != len(b).
+func (file *File) Write(b []byte) (n int, err Error) {
+	if file == nil {
+		return 0, EINVAL
+	}
+	n, e := syscall.Write(file.fd, b)
+	if n < 0 {
+		n = 0
+	}
+	if e == syscall.EPIPE {
+		file.nepipe++
+		if file.nepipe >= 10 {
+			Exit(syscall.EPIPE)
+		}
+	} else {
+		file.nepipe = 0
+	}
+	if e != 0 {
+		err = &PathError{"write", file.name, Errno(e)}
+	}
+	return n, err
+}
+
+// WriteAt writes len(b) bytes to the File starting at byte offset off.
+// It returns the number of bytes written and an Error, if any.
+// WriteAt returns a non-nil Error when n != len(b).
+func (file *File) WriteAt(b []byte, off int64) (n int, err Error) {
+	if file == nil {
+		return 0, EINVAL
+	}
+	for len(b) > 0 {
+		m, e := syscall.Pwrite(file.fd, b, off)
+		if e != 0 {
+			err = &PathError{"write", file.name, Errno(e)}
+			break
+		}
+		n += m
+		b = b[m:]
+		off += int64(m)
+	}
+	return
+}
+
+// Seek sets the offset for the next Read or Write on file to offset, interpreted
+// according to whence: 0 means relative to the origin of the file, 1 means
+// relative to the current offset, and 2 means relative to the end.
+// It returns the new offset and an Error, if any.
+func (file *File) Seek(offset int64, whence int) (ret int64, err Error) {
+	r, e := syscall.Seek(file.fd, offset, whence)
+	if e == 0 && file.dirinfo != nil && r != 0 {
+		e = syscall.EISDIR
+	}
+	if e != 0 {
+		return 0, &PathError{"seek", file.name, Errno(e)}
+	}
+	return r, nil
+}
+
+// WriteString is like Write, but writes the contents of string s rather than
+// an array of bytes.
+func (file *File) WriteString(s string) (ret int, err Error) {
+	if file == nil {
+		return 0, EINVAL
+	}
+	b := syscall.StringByteSlice(s)
+	b = b[0 : len(b)-1]
+	return file.Write(b)
+}
+
+// Pipe returns a connected pair of Files; reads from r return bytes written to w.
+// It returns the files and an Error, if any.
+func Pipe() (r *File, w *File, err Error) {
+	var p [2]int
+
+	// See ../syscall/exec.go for description of lock.
+	syscall.ForkLock.RLock()
+	e := syscall.Pipe(p[0:])
+	if e != 0 {
+		syscall.ForkLock.RUnlock()
+		return nil, nil, NewSyscallError("pipe", e)
+	}
+	syscall.CloseOnExec(p[0])
+	syscall.CloseOnExec(p[1])
+	syscall.ForkLock.RUnlock()
+
+	return NewFile(p[0], "|0"), NewFile(p[1], "|1"), nil
+}
+
+// Mkdir creates a new directory with the specified name and permission bits.
+// It returns an error, if any.
+func Mkdir(name string, perm uint32) Error {
+	e := syscall.Mkdir(name, perm)
+	if e != 0 {
+		return &PathError{"mkdir", name, Errno(e)}
+	}
+	return nil
+}
+
+// Stat returns a FileInfo structure describing the named file and an error, if any.
+// If name names a valid symbolic link, the returned FileInfo describes
+// the file pointed at by the link and has fi.FollowedSymlink set to true.
+// If name names an invalid symbolic link, the returned FileInfo describes
+// the link itself and has fi.FollowedSymlink set to false.
+func Stat(name string) (fi *FileInfo, err Error) {
+	var lstat, stat syscall.Stat_t
+	e := syscall.Lstat(name, &lstat)
+	if e != 0 {
+		return nil, &PathError{"stat", name, Errno(e)}
+	}
+	statp := &lstat
+	if lstat.Mode&syscall.S_IFMT == syscall.S_IFLNK {
+		e := syscall.Stat(name, &stat)
+		if e == 0 {
+			statp = &stat
+		}
+	}
+	return fileInfoFromStat(name, new(FileInfo), &lstat, statp), nil
+}
+
+// Lstat returns the FileInfo structure describing the named file and an
+// error, if any.  If the file is a symbolic link, the returned FileInfo
+// describes the symbolic link.  Lstat makes no attempt to follow the link.
+func Lstat(name string) (fi *FileInfo, err Error) {
+	var stat syscall.Stat_t
+	e := syscall.Lstat(name, &stat)
+	if e != 0 {
+		return nil, &PathError{"lstat", name, Errno(e)}
+	}
+	return fileInfoFromStat(name, new(FileInfo), &stat, &stat), nil
+}
+
+// Chdir changes the current working directory to the named directory.
+func Chdir(dir string) Error {
+	if e := syscall.Chdir(dir); e != 0 {
+		return &PathError{"chdir", dir, Errno(e)}
+	}
+	return nil
+}
+
+// Chdir changes the current working directory to the file,
+// which must be a directory.
+func (f *File) Chdir() Error {
+	if e := syscall.Fchdir(f.fd); e != 0 {
+		return &PathError{"chdir", f.name, Errno(e)}
+	}
+	return nil
+}
+
+// Remove removes the named file or directory.
+func Remove(name string) Error {
+	// System call interface forces us to know
+	// whether name is a file or directory.
+	// Try both: it is cheaper on average than
+	// doing a Stat plus the right one.
+	e := syscall.Unlink(name)
+	if e == 0 {
+		return nil
+	}
+	e1 := syscall.Rmdir(name)
+	if e1 == 0 {
+		return nil
+	}
+
+	// Both failed: figure out which error to return.
+	// OS X and Linux differ on whether unlink(dir)
+	// returns EISDIR, so can't use that.  However,
+	// both agree that rmdir(file) returns ENOTDIR,
+	// so we can use that to decide which error is real.
+	// Rmdir might also return ENOTDIR if given a bad
+	// file path, like /etc/passwd/foo, but in that case,
+	// both errors will be ENOTDIR, so it's okay to
+	// use the error from unlink.
+	// For windows syscall.ENOTDIR is set
+	// to syscall.ERROR_DIRECTORY, hopefully it should
+	// do the trick.
+	if e1 != syscall.ENOTDIR {
+		e = e1
+	}
+	return &PathError{"remove", name, Errno(e)}
+}
+
+// LinkError records an error during a link or symlink or rename
+// system call and the paths that caused it.
+type LinkError struct {
+	Op    string
+	Old   string
+	New   string
+	Error Error
+}
+
+func (e *LinkError) String() string {
+	return e.Op + " " + e.Old + " " + e.New + ": " + e.Error.String()
+}
+
+// Link creates a hard link.
+func Link(oldname, newname string) Error {
+	e := syscall.Link(oldname, newname)
+	if e != 0 {
+		return &LinkError{"link", oldname, newname, Errno(e)}
+	}
+	return nil
+}
+
+// Symlink creates a symbolic link.
+func Symlink(oldname, newname string) Error {
+	e := syscall.Symlink(oldname, newname)
+	if e != 0 {
+		return &LinkError{"symlink", oldname, newname, Errno(e)}
+	}
+	return nil
+}
+
+// Readlink reads the contents of a symbolic link: the destination of
+// the link.  It returns the contents and an Error, if any.
+func Readlink(name string) (string, Error) {
+	for len := 128; ; len *= 2 {
+		b := make([]byte, len)
+		n, e := syscall.Readlink(name, b)
+		if e != 0 {
+			return "", &PathError{"readlink", name, Errno(e)}
+		}
+		if n < len {
+			return string(b[0:n]), nil
+		}
+	}
+	// Silence 6g.
+	return "", nil
+}
+
+// Rename renames a file.
+func Rename(oldname, newname string) Error {
+	e := syscall.Rename(oldname, newname)
+	if e != 0 {
+		return &LinkError{"rename", oldname, newname, Errno(e)}
+	}
+	return nil
+}
+
+// Chmod changes the mode of the named file to mode.
+// If the file is a symbolic link, it changes the mode of the link's target.
+func Chmod(name string, mode uint32) Error {
+	if e := syscall.Chmod(name, mode); e != 0 {
+		return &PathError{"chmod", name, Errno(e)}
+	}
+	return nil
+}
+
+// Chmod changes the mode of the file to mode.
+func (f *File) Chmod(mode uint32) Error {
+	if e := syscall.Fchmod(f.fd, mode); e != 0 {
+		return &PathError{"chmod", f.name, Errno(e)}
+	}
+	return nil
+}
+
+// Chown changes the numeric uid and gid of the named file.
+// If the file is a symbolic link, it changes the uid and gid of the link's target.
+func Chown(name string, uid, gid int) Error {
+	if e := syscall.Chown(name, uid, gid); e != 0 {
+		return &PathError{"chown", name, Errno(e)}
+	}
+	return nil
+}
+
+// Lchown changes the numeric uid and gid of the named file.
+// If the file is a symbolic link, it changes the uid and gid of the link itself.
+func Lchown(name string, uid, gid int) Error {
+	if e := syscall.Lchown(name, uid, gid); e != 0 {
+		return &PathError{"lchown", name, Errno(e)}
+	}
+	return nil
+}
+
+// Chown changes the numeric uid and gid of the named file.
+func (f *File) Chown(uid, gid int) Error {
+	if e := syscall.Fchown(f.fd, uid, gid); e != 0 {
+		return &PathError{"chown", f.name, Errno(e)}
+	}
+	return nil
+}
+
+// Truncate changes the size of the file.
+// It does not change the I/O offset.
+func (f *File) Truncate(size int64) Error {
+	if e := syscall.Ftruncate(f.fd, size); e != 0 {
+		return &PathError{"truncate", f.name, Errno(e)}
+	}
+	return nil
+}
+
+// Sync commits the current contents of the file to stable storage.
+// Typically, this means flushing the file system's in-memory copy
+// of recently written data to disk.
+func (file *File) Sync() (err Error) {
+	if file == nil {
+		return EINVAL
+	}
+	if e := syscall.Fsync(file.fd); e != 0 {
+		return NewSyscallError("fsync", e)
+	}
+	return nil
+}
+
+// Chtimes changes the access and modification times of the named
+// file, similar to the Unix utime() or utimes() functions.
+//
+// The argument times are in nanoseconds, although the underlying
+// filesystem may truncate or round the values to a more
+// coarse time unit.
+func Chtimes(name string, atime_ns int64, mtime_ns int64) Error {
+	var utimes [2]syscall.Timeval
+	utimes[0] = syscall.NsecToTimeval(atime_ns)
+	utimes[1] = syscall.NsecToTimeval(mtime_ns)
+	if e := syscall.Utimes(name, utimes[0:]); e != 0 {
+		return &PathError{"chtimes", name, Errno(e)}
+	}
+	return nil
+}